Evolutional algorithm based cascade long reach passive optical networks planning

In this paper, we propose a mathematical model for long reach Passive Optical Networks (PON) planning. The model considers the traffic demand, user requirements and physical constraints. It can support conventional star-like topologies as well as cascade PON networks. Then a two-stage evolutional algorithm is described to solve this problem. The first stage was to find a proper splitter candidate site set, composing the outer loop. The second stage aimed to get the optimal topology when the splitter locations were selected, composing the internal loop. In this algorithm, the Prüfer sequence is used to build up a one-to-one correspondence between a PON network configuration and a chromosome. Compared with the results obtained by the enumeration method, the proposed model and algorithm are shown to be effective and accurate.